package com.jbm.util.bean;

/*
 * Copyright 2013-2015 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import cn.hutool.core.lang.Assert;
import com.jbm.util.StringUtils;

import java.util.ArrayList;
import java.util.List;

/**
 * Value object to represent a Version consisting of major, minor and bugfix
 * part.
 * 
 * @author Oliver Gierke
 */
public class Version implements Comparable<Version> {

	private static final String VERSION_PARSE_ERROR = "Invalid version string! Could not parse segment %s within %s.";

	private int major;
	private int minor;
	private int bugfix;
	private int build;

	/**
	 * Creates a new {@link Version} from the given integer values. At least one
	 * value has to be given but a maximum of 4.
	 * 
	 * @param parts
	 *            must not be {@literal null} or empty.
	 */
	public Version(int... parts) {
		Assert.notNull(parts);
		Assert.isTrue(parts.length > 0 && parts.length < 5);

		this.major = parts[0];
		this.minor = parts.length > 1 ? parts[1] : 0;
		this.bugfix = parts.length > 2 ? parts[2] : 0;
		this.build = parts.length > 3 ? parts[3] : 0;

		Assert.isTrue(major >= 0, "Major version must be greater or equal zero!");
		Assert.isTrue(minor >= 0, "Minor version must be greater or equal zero!");
		Assert.isTrue(bugfix >= 0, "Bugfix version must be greater or equal zero!");
		Assert.isTrue(build >= 0, "Build version must be greater or equal zero!");
	}

	/**
	 * Parses the given string representation of a version into a
	 * {@link Version} object.
	 * 
	 * @param version
	 *            must not be {@literal null} or empty.
	 * @return
	 */
	public static Version parse(String version) {

		Assert.notEmpty(version);

		String[] parts = version.trim().split("\\.");
		int[] intParts = new int[parts.length];

		for (int i = 0; i < parts.length; i++) {

			String input = i == parts.length - 1 ? parts[i].replaceAll("\\D.*", "") : parts[i];

			if (StringUtils.hasText(input)) {
				try {
					intParts[i] = Integer.parseInt(input);
				} catch (IllegalArgumentException o_O) {
					throw new IllegalArgumentException(String.format(VERSION_PARSE_ERROR, input, version), o_O);
				}
			}
		}

		return new Version(intParts);
	}

	/**
	 * 创建第一个版本
	 * 
	 * @return
	 */
	public static Version create() {
		return new Version(1, 0, 0, 0);
	}

	/**
	 * Returns whether the current {@link Version} is greater (newer) than the
	 * given one.
	 * 
	 * @param version
	 * @return
	 */
	public boolean isGreaterThan(Version version) {
		return compareTo(version) > 0;
	}

	/**
	 * Returns whether the current {@link Version} is greater (newer) or the
	 * same as the given one.
	 * 
	 * @param version
	 * @return
	 */
	public boolean isGreaterThanOrEqualTo(Version version) {
		return compareTo(version) >= 0;
	}

	/**
	 * Returns whether the current {@link Version} is the same as the given one.
	 * 
	 * @param version
	 * @return
	 */
	public boolean is(Version version) {
		return equals(version);
	}

	/**
	 * Returns whether the current {@link Version} is less (older) than the
	 * given one.
	 * 
	 * @param version
	 * @return
	 */
	public boolean isLessThan(Version version) {
		return compareTo(version) < 0;
	}

	/**
	 * Returns whether the current {@link Version} is less (older) or equal to
	 * the current one.
	 * 
	 * @param version
	 * @return
	 */
	public boolean isLessThanOrEqualTo(Version version) {
		return compareTo(version) <= 0;
	}

	/**
	 * 大版本升级
	 */
	public synchronized Version major() {
		this.major++;
		return this;
	}

	/**
	 * 小版本升级
	 */
	public synchronized Version minor() {
		if (minor >= 99) {
			major();
			minor = 0;
		} else {
			this.minor++;
		}
		return this;
	}

	/**
	 * 修正升级
	 */
	public synchronized Version bugfix() {
		if (bugfix >= 99) {
			minor();
			bugfix = 0;
		} else {
			this.bugfix++;
		}
		return this;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see java.lang.Comparable#compareTo(java.lang.Object)
	 */
	public int compareTo(Version that) {

		if (that == null) {
			return 1;
		}

		if (major != that.major) {
			return major - that.major;
		}

		if (minor != that.minor) {
			return minor - that.minor;
		}

		if (bugfix != that.bugfix) {
			return bugfix - that.bugfix;
		}

		if (build != that.build) {
			return build - that.build;
		}

		return 0;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see java.lang.Object#equals(java.lang.Object)
	 */
	@Override
	public boolean equals(Object obj) {

		if (this == obj) {
			return true;
		}

		if (!(obj instanceof Version)) {
			return false;
		}

		Version that = (Version) obj;

		return this.major == that.major && this.minor == that.minor && this.bugfix == that.bugfix && this.build == that.build;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see java.lang.Object#hashCode()
	 */
	@Override
	public int hashCode() {

		int result = 17;
		result += 31 * major;
		result += 31 * minor;
		result += 31 * bugfix;
		result += 31 * build;
		return result;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see java.lang.Object#toString()
	 */
	@Override
	public String toString() {

		List<Integer> digits = new ArrayList<Integer>();
		digits.add(major);
		digits.add(minor);

		// if (build != 0 || bugfix != 0) {
		digits.add(bugfix);
		// }

		if (build != 0) {
			digits.add(build);
		}

		return StringUtils.collectionToDelimitedString(digits, ".");
	}

	/**
	 * 转换成数字型
	 * 
	 * @return
	 */
	public int toNumber() {
		int result = 0;
		result += build;
		result += bugfix * 100;
		result += minor * 100 * 100;
		result += major * 100 * 100 * 100;
		// final String xxx = StringUtils.join(new Object[] { major, minor,
		// bugfix, build });
		// return NumberUtils.toInt(xxx);
		return result;
	}

}
